What are the main characteristics of DC motor?

Generally, three characteristic curves are considered important for DC motors which are, (i) Torque vs. armature current, (ii) Speed vs. armature current and (iii) Speed vs. torque.

What are the characteristics of AC motor and DC motor?

A three-phase AC motor is self-starting but a single-phase AC motor requires a starting mechanism. DC motors are always self-starting in nature. In AC motors, the armature is stationary while the magnetic field rotates. In DC motors, the armature rotates while the magnetic field remains stationary.

Which of the following are characteristics of a DC generator?

Open Circuit Characteristic (O.C.C.)

Open circuit characteristic is also known as magnetic characteristic or no-load saturation characteristic. This characteristic shows the relation between generated emf at no load (E0) and the field current (If) at a given fixed speed.

What are the key characteristics of the DC shunt motor?

1.17, four important characteristics of a dc shunt motor, namely, torque, speed, armature current, and efficiency, each plotted against the useful output power, are shown. These curves are also known as performance curves of a motor.

What you have observed in characteristics of DC shunt motor?

DC shunt motor: In case of DC shunt motor, the flux per pole is considered to be constant, torque increases with the increase of load current. If the load current increases then the armature current also be increased and the speed slightly falls due to increase in voltage drop in armature.

What are the characteristics of a separately excited DC generator?

The external characteristic of the separately excited DC generator is obtained by subtracting the drops due to ohmic loss (Ia Ra) in the armature from generated voltage (Eg). Terminal voltage(V) = Eg – Ia Ra. This curve gives the relation between the terminal voltage (V) and load current.

What are the main parts of a DC machine?

Parts of a DC Generator
  • Stator. The main function of the stator is to provide magnetic fields where the coil spins. …
  • Rotor. A rotor in a DC machine includes slotted iron laminations with slots that are stacked to shape a cylindrical armature core. …
  • Armature Windings. …
  • Yoke. …
  • Poles. …
  • Pole Shoe. …
  • Commutator. …
  • Brushes.

What are the characteristics of DC shunt generator?

A shunt generator is a type of dc generator in which the field winding is connected in parallel with the armature winding so that the terminal voltage of the generator is applied across it. The shunt field winding has many turns of fine wire having high resistance.

What are the characteristics of single-phase motor?

Its low starting torque is typically 25 to 75% of full-load torque. It is a high slip motor with running speed 7 to 10% below synchronous speed, Also, it is very inefficient, usually below 20%. Low initial cost suits shaded-pole motors to low-horsepower or light-duty applications.

What are the characteristics of AC motor?

An AC motor is an electric motor driven by an alternating current (AC). The AC motor commonly consists of two basic parts, an outside stator having coils supplied with alternating current to produce a rotating magnetic field, and an inside rotor attached to the output shaft producing a second rotating magnetic field.

What are the characteristics of induction motor?

The induction motor torque varies from zero to full load torque as the slip varies. The slip varies from zero to one. It is zero at no load and one at standstill. From the curve it is seen that the torque is directly proportional to the slip.

What are the uses of motor?

Uses of an Electric Motor
  • Drills.
  • Water Pumps.
  • Hard Disc Drives.
  • Washing Machines.
  • Industrial Equipment.

What is DC machine?

A DC motor is defined as a class of electrical motors that convert direct current electrical energy into mechanical energy. From the above definition, we can conclude that any electric motor that is operated using direct current or DC is called a DC motor.

What is the principle of DC motor?

The basic working principle of the DC motor is that whenever a current carrying conductor places in the magnetic field, it experiences a mechanical force. Fleming’s left-hand rule and its magnitude decide the direction of this force.